The present invention relates to the processing devices. More particularly, the present invention relates to the use of spectrometers in semiconductor processing devices.
In the manufacturing processes, which use a plasma in a plasma chamber, monitoring the process within the plasma chamber is desirable.
To facilitate discussion, FIG. 1 is a schematic illustration of a prior art plasma processing device 10 and spectrometer 12. The plasma processing device 10 may comprise a plasma processing chamber 14 and a device computer 16. The spectrometer 12 may be controlled by a spectrometer computer 17. The spectrometer computer 17 may be linked to the device computer 16 by a serial connection 18, such as an RS-232 connection, which may have a communications speed of 9600 bytes per second. The plasma processing chamber 14 may support a power source 19. The spectrometer 12 may comprise a diffraction grating 22 and a one dimensional charge coupled device (CCD) array 23. The array may have between 1,000-3,000 elements.
Since the spectrometer 12 is controlled by a spectrometer computer 17 that is linked to the device computer 16 by a serial connection 18, it may be difficult to get large amounts of data provided by the 1000-3000 elements of the CCD array at a scan rate on the order of 200 scans per seconds to the device computer 16 in real time so that the device computer 16 can analyze the data and control the process in the plasma process chamber 14. Therefore, in the prior art, the data from the spectrometer may be reduced by the spectrometer computer 17. The reduced data may then be transmitted to the device computer 16. In addition, the spectrometer computer 17 may need to be programmed individually from the device computer 16 increasing the set up time. For example, to reduce data size, the spectrometer computer 17 may be programmed to only transfer data regarding a narrow spectrum. The device computer 16 would also need to be programmed to accommodate data from the narrow spectrum. To program the spectrometer computer 17, the spectrometer computer 17 may require its own input and output hardware, such as a display and keyboard, which increases the cost and footprint of the overall hardware. In addition, the transfer of data between the spectrometer computer 17 and the device computer 16 may take CPU time of the device computer 16.
In view of the foregoing, it is desirable to provide a plasma processing device with a spectrometer that is able to receive and process large amounts of data from the spectrometer in real time, to allow real time control of the plasma processing device as a result of the large amounts of data from the spectrometer.
The invention relates, in one embodiment, to a plasma processing device, comprising: a plasma processing chamber; a computer connected to the plasma processing device, comprising: a first CPU; a CPU bus connected to the first CPU; and a first input board connected to the CPU bus; and a spectrometer connected to the input board.
These and other features of the present invention will be described in more detail below in the detailed description of the invention and in conjunction with the following figures.